This invention relates generally to electrical connectors, and more particularly, to electrical connectors with a horizontal ground plane.
Modern electronics use high frequency and high speed connectors particularly for use in interconnecting circuitry in electronic devices. These electronic devices typically include printed circuit boards which are used to couple data among these various electronic devices. In order to provide for a higher density of connectors on a printed circuit board, surface mount technology is utilized. With surface mounting, conductive pads located on the printed circuit board can be closely spaced, thereby allowing more contacts to be mounted in the same area of the board. Signal conductors are coupled to the conductive pads and transmit the data across the boards. Typically, the signal conductors will be coupled to the printed circuit board as a differential pair.
Due to continuing trends toward miniaturization, signal conductors are placed in closer proximity to one another, thereby leading to the potential for crosstalk between neighboring conductive contacts in different signal pairs. Thus, known connectors typically include shielding or ground planes between the signal conductors to reduce crosstalk therebetween. These connectors have a mating interface sub-assembly coupled to the end of the printed circuit board to interface with the opposing electronic device. The sub-assembly includes a plurality of stamped and formed metal contacts extending outwardly from the printed circuit board and a plurality of ground planes extending vertically and interposed between the metal contacts. However, these connectors require additional assembly time and fabrication costs.
Connectors have also been proposed that remove the mating interface sub-assembly and instead configure one edge of the printed circuit board to operate as a separable interface. The separable interface edge of the printed circuit board includes contact pads on one or both sides of the printed circuit board. The contact pads are arranged in differential pairs such that the contact pads associated with a differential pair are next to one another and located on the same side of the printed circuit board. Traces extending from the contact pads of a differential pair are also located directly next to one another. The contact pads and traces associated with one differential pair convey signals that are related to one another and more specifically convey signals that are the inverse of one another.
However, certain problems remain in connection with the signal performance.